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The maximum value of E in an electromagnetic wave is equal to 18 V m⁻¹. Thus the maximum value of B is ______.

Asked in RS Academy GUJCET booklet · E0 = cB0 and E/B = c

• (1) 3×10⁻⁶ T
• (2) 6×10⁻⁸ T
• (3) 9×10⁻⁹ T
• (4) 2×10⁻¹⁰ T

Step-by-step solution

Why the other options are wrong

• (1) comes from no single slip produces 3×10⁻⁶ T. Sanity check: B₀=(E₀)/c=(18)/(3×10⁸)=6×10⁻⁸ T, fifty times smaller than this option.
• (3) 9×10⁻⁹ T is (E₀)/c for E₀=2.7 V m⁻¹, not for 18 V m⁻¹.
• (4) 2×10⁻¹⁰ T is three hundred times smaller than (E₀)/c; no step in this calculation produces it.

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